A senior French police officer has claimed that the interior ministry “harassed” her into altering a security report from the deadly terrorist attack in Nice.

Sandra Bertin, the officer in charge of Nice's CCTV control room, told the Journal du Dimanche newspaper on Sunday that an unnamed interior ministry official contacted her after the attack and pressured her into altering her report for the night of the incident.

On July 14, a truck driver plowed through a Bastille Day crowd in Nice, killing 84 people and wounding 200 others.

Bertin claims that she was "harassed for an hour" by the official who wanted her to detail the presence of local and national police at the fireworks event where the carnage took place.

"The national police were perhaps there, but I couldn't see them on the video," she said, adding, "He ordered me to put in (the report) the specific positions of the national police which I had not seen on the screen."

She also said that the person from the ministry told her to email her report in a “modifiable form … so they didn’t have to type it all out again.”

France’s Interior Minister Bernard Cazeneuve (seen below) has dismissed the claims and has announced that he will sue Bertin for defamation.

“It will be very useful if Madame Sandra Bertin could be questioned by the investigators and could give them the names and positions of the people she is accusing, the emails she is talking about and their contents,” he said in a statement.

“Unworthy accusations are part of the virulent polemic that certain elected representatives in Nice have wanted to encourage and feed every day since the terrible July 14 attack,” he added.

The 31-year-old Franco-Tunisian assailant in the attack, who was later shot dead by police, was identified as Mohamed Lahouaiej-Bouhlel.

People walk past flowers, candles and messages laid on the Promenade des Anglais seafront in Nice on July 18, 2016, in tribute to the victims of the deadly attack which killed 84 people on July 14. (AFP)

The Daesh Takfiri terrorist group later claimed responsibility for the deadly attack in Nice. But, Paris prosecutor Francois Molins said that no direct evidence has been found to link the attacker to the terrorists.

The European country has been in a state of emergency since last November, when assailants struck at least six different venues in and around the capital Paris, leaving 130 people dead and over 350 others injured. Daesh claimed responsibility for the horrendous assaults.

On Wednesday, the French parliament extended the country's state of emergency for another six months.